Abstract: The effect of graphite on the wear resistance of hybrid Cu/TiC-Gr composites was studied. The composites were fabricated by liquid infiltration of copper in ceramic porous preforms. The composites showed a homogeneous distribution of the reinforcement in the matrix, but some lack of adherence of the graphite to the matrix. The composite with 1 vol.% graphite showed a density of 6.25 g/cm3 and a residual porosity less to 4%. The hardness was 326 HV and the elastic modulus 332 GPa. Because of the addition of graphite, the hardness of the composite decreased compared with that of the composite made of a pure Cu matrix. The dry-sliding wear behavior study concluded that the wear resistance of the hybrid composite increased slightly compared with the Cu/TiC system. The coefficient of friction presented a similar behavior for both materials, having an approximate value of 1.3. The wear mechanisms observed for the Cu/TiC-Gr composites were adhesive, abrasive, delamination and oxidation deterioration, where the combination of surface oxides and the plastic deformation of the matrix play a predominant role.
Authors: Carlos A. Leon-Patino, Alejandro Miranda-López, Ena A. Aguilar-Reyes, and Gabriel Rodríguez-Ortiz
Keywords: Hybrid composite, Wear, Infiltration, Copper matrix, Graphite, Titanium carbide